A conventional color cathode-ray tube comprises a glass bulb, a shadow mask, and a deflection yoke. The glass bulb comprises a face-plate with stripe-like phosphors for red, green and blue on its inner face, a funnel portion connected to the rear part of the face-plate, and a neck portion formed at the rear of the funnel portion. Inside the neck portion, an inline electron gun for emitting electron beams is provided. The shadow mask has a plurality of openings disposed corresponding to the stripe direction of the phosphors for each color on the face-plate. The deflection yoke is provided on the peripheral surfaces of the funnel portion and the neck portion.
In a process of manufacturing a color cathode-ray lube for ensuring color reproduction, a face-plate and a shadow mask are considered as a pair of components, and phosphors for red, green, and blue are formed on the face-plate by three sequential steps of: applying phosphors onto the face-plate; attaching the shadow mask onto the face-plate and exposing the face-plate through openings of the shadow mask; and detaching the shadow mask from the face-plate, which is then developed.
In a process of manufacturing a color cathode-ray tube for reducing manufacturing cost, the face-plate and the shadow mask are considered as separate components, and phosphors for red, green, and blue are formed on the face-plate by a screen printing method without using a shadow mask.
However, in the conventional color-cathode ray tube, the former manufacturing process requires three steps of the application, exposure, and development in addition to the attachment and detachment of the shadow mask onto and from the face-plate in forming the phosphors for each color as described above. Therefore, complex manufacturing equipment and a long manufacturing time are required, thus increasing the cost of the color cathode-ray tube. On the other hand, in the latter manufacturing process, when a shadow mask is attached onto a face-plate, the attachment error of the shadow mask to the face-plate, particularly the attachment error that occurs when the stripe-like openings of the shadow mask tilt with respect to the stripe direction of the phosphors, cannot be corrected, thus causing unevenness in color. In addition, the color reproduction cannot be ensured easily due to insufficient beam landing tolerance.